/*
 * Created on Jul 15, 2007
 * Created by Paul Gardner
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

package org.gudy.azureus2.core3.disk.impl.piecemapper.impl;

import org.gudy.azureus2.core3.disk.impl.DiskManagerFileInfoImpl;
import org.gudy.azureus2.core3.disk.impl.piecemapper.DMPieceList;
import org.gudy.azureus2.core3.disk.impl.piecemapper.DMPieceMap;
import org.gudy.azureus2.core3.disk.impl.piecemapper.DMPieceMapEntry;
import org.gudy.azureus2.core3.torrent.TOTorrent;

public class DMPieceMapSimple implements DMPieceMap {
    final private int piece_length;
    final private int piece_count;
    final private int last_piece_length;

    final private DiskManagerFileInfoImpl file;

    protected DMPieceMapSimple(TOTorrent torrent, DiskManagerFileInfoImpl _file) {
        piece_length = (int) torrent.getPieceLength();

        piece_count = torrent.getNumberOfPieces();

        int lpl = (int) (torrent.getSize() % piece_length);

        if (lpl == 0) {

            lpl = piece_length;
        }

        last_piece_length = lpl;

        file = _file;
    }

    public DMPieceList getPieceList(int piece_number) {
        return (new pieceList(piece_number));
    }

    protected class pieceList implements DMPieceList, DMPieceMapEntry {
        private int piece_number;

        protected pieceList(int _piece_number) {
            piece_number = _piece_number;
        }

        public int size() {
            return (1);
        }

        public DMPieceMapEntry get(int index) {
            return (this);
        }

        public int getCumulativeLengthToPiece(int file_index) {
            return (getLength());
        }

        // map entry

        public DiskManagerFileInfoImpl getFile() {
            return (file);
        }

        public long getOffset() {
            return (((long) piece_number) * piece_length);
        }

        public int getLength() {
            if (piece_number == piece_count - 1) {

                return (last_piece_length);
            } else {

                return (piece_length);
            }
        }
    }
}
